Polyphenyl ethers containing an extreme pressure additive



United. States Patent 3,139,548 PQLYPHENYL ETHERS CQNTADIING AN EX'I'REME PRESSURE ADDITIVE Glenn R. Wilson, Cambridge, and John R. Stemnisiri, Swampscott, Mass., assignors to Monsanto Research Corporation, St. Louis, M0,, a corporation of Delaware No Drawing. Filed Apr. 30, 1963, Ser. No. 276,976

11 Claims. (Cl. 252- 515) This invention relates to lubricating compositions, and more particularly, provides novel lubricating compositions comprising a base fluid and including as an additive a diaminodichlorobenzoquinone.

For lubrication in the temperature range up to 300 or 400 F., mineral oils can be used eflectively. However, design requirements in recent years have demanded the development of lubricants effective under conditions of stress, including higher temperatures such as ternperatures in the range of 400 or 500 F. up to1000 F., as well as stress conditions such as ultra-high pressure loads, exposure to ionizing radiation, and the like. Mineral oil compositions cannot meet this demand, and consequently synthetic base fluids have been developed, such as ester and other base fluids. These oxygenated base fluids have thermal stability superior to the hydrocarbon fluids such as the mineral oils, but on the other hand, their inherent lubricating properties are generally inferior to those of the mineral oils.

In the lubricant art, experience over the years has gradually accumulated a large fund of information on the effect of various types of additives on mineral oils, and it has been found that lubricity can be enhanced by the combination of additives with mineral oil base fluids.v

However, in development of lubricant compositions based on synthetic base fluids, it has been established that there is no reliable correlation between activity of an additive in a mineral oil and its activity in one of the synthetic base oils. Thus, there is still an unsatisfied demand for the development of compositions useful as functional fluids and particularly as lubricants in the temperature range of 400 or 500 F. and above.

It is an object of this invention to provide novel functional compositions having improved lubricant properties and useful in the temperature range of 400 or 500 F. and above. l i

It is a particular object of this invention to provide novel high temperature lubricant compositions having improved extreme pressure and anti-wear proper-ties and useful in the temperature range of 400 of 500 F. and above.

These and other objects will become evident on a consideration of the following specification and claims.

It has now been found that combining a base oil of lubricating viscosity, which remains in the liquid phase up to at least about 500 F., with a diaminodichlorobenzoquinone having an aromatic radical attached to each of the amino nitrogen atoms selected from the class consisting of aryl and arylcarbonyl radicals, provides valuable high temperature lubricant compositions having enhanced lubricating characteristics.

The presently provided lubricant compositions are particularly valuable for the lubrication of moving, frictionally contacting metal surfaces under conditions of stress such as exposure to elevated temperatures, high loads, and the like. It is to be appreciated, however, they are also valuable over a wide spectrum of conditions. As will become evident hereinafter, for example, the presently provided additives decrease the wear exhibited by friotionally contacting metal surfaces even at lower temperatures such as between 100 and 200 F.

In particular, the present invention provides novel, valuable lubricating compositions wherein the stated ben- 3,13%,548 Patented June 15, 1.965

ice

zoquinone compounds are combined with a base fluid comprising a polyphenyl ether, such lubricant compositions having superior lubricity characteristics. The polyphenyl others are known compounds which have found wide application as functional fluids owing to their Very good thermal stability, lubricity, and resistance to foam. For example, they have been found to be valuable as hydraulic fluids, heat exchange media, atomic reactor coolants, diffusion pump fluids, lubricants in motor operation generally, and specifically as jet engine lubricants. The stated polyphenyl ethers may be employed to provide effective lubrication at operating temperatures as high as 600 F. and above, and with the improved compositions comprising such polyphenyl others as base fluids in accordance with this invention, good lubrication can be provided even for heavily loaded metal surfaces in frictional contact at such elevated temperatures.

The benzoquinone additives combined with lubricant base fluids to provide lubricant compositions in accordance with this invention are diaminodichlorobenzoquinones wherein an aromatic radical is attached to each amino group, either directly or through a carbonyl group.

In general, they are 1,4-benzoquinones, represented by the formula where Ar and Ar are aryl radicals, n and m are integers selected from 0 and l, and R and R are selected from the class consisting of hydrogen, saturated aliphatic hydrocarbon of up to 6 carbon atoms, and a carbonyl group linked to the adjacent aryl radical. The aryl radicals are carbocyclic, benzene or naphthalene, rings linked to the nitrogen atoms, directly or through a carbonyl group, by a ring carbon atom: they may be hydrocarbon or carry any of a wide variety of substituents. This type of compound is readily prepared by condensation of chloranil (tetrachloro-1,4-benzoquinone) with the corresponding aromatic amino, amido or imido compound.

Where the compounds of the invention have an aryl radical directly attached to each amino. snbstituent on the benz'oquinone ring, they are dichlorodianiliriobenzoquinones and related dichlorodiarylaminobenzoquinones. Thus, illustrative of this type of presently useful additive are V ides).

2,5-dichloro-3,6-bis(4-rnethyl-3 nitroanilino)benzoqui- 7 none, V 2,5-dichloro-3,6=bis(4-bromo-2-nitroanilino)benzoquinone, 2,5-dichloro-3,6-bis(2,4-dibromo-6-nitroanilino)benzoquinone, Y

2,5-dichloro-3,G bis(4-acetamidoanil-ino)ben2oquinone,'

2,5-dich1oro-3,6 ois(2,4,5-trichloroanilino}benzoquinone,

I 2,5-dichlro-3,6-bis(2,4-dichloroenilino)benzoquinone, I 2,5-dichloro-3,6-'bis-(4-sulfamylanilino)benzoquinone,

2,5-dichloro-3,6 bis(4-rnethyl-2 nitroanilino)benzoquinone, 2,5-dichloro-3,6-bis(2-chloro-4-nitroanilino)benzoquinone, 2,5-dichloro-3,6-bis(2,6-dichloro-4-nitroanilino)benioquinone, v 2,5 clichloro-3,6-bis(2bremo-4-methyl-6-nitroanilino) benzoquinone, r 2,5-dichloro-3,6-bis(l iodoanilino)benzoquinone,

none, a 2,'5-dichloro-3,'6bis(4-acetylanilino)benzoquinone, 2,5 -dichloro-3 ,6-bis(2-carbomethoxyanilino)benzoquinone, 2,5-dich-loro-3,6 bis(4-sulfo-6-nitro-'1-naphthy1amino) benzoquinone,

j2,5-dichloro-3,6-bis(2-carboXy-3-sulfo -4ohloroanilino) benzoquinone,

I 2,5-di-chloro-3,6-bis(4-diethylaminoanilino)benzoqui The presently employed additives wherein a carbonyl group intervenes between theamino substituent or the central benzoquinone ring and the aryl su'bsti-tuent of the amino group are dichlorobis(arylcanboxamido)benzoqui nones (NJJT (dioxodichlorophenylenebiSJarylCarbQXam- Thus, illustrative of the presently useful .compounds are r 2,5-dichloro -3,6-dibenzamido-benzoquinone, 2,5-dichloro-3,6-bisQ2-methylbenzarnido)-benzoquinone, 2,5-dich1oro-3,6 bis(4-rnethylbenzamido)benzoquinone, 2,5-diehloro-3,6 bis(2,4-dimethylbenzamido)henzoqui- .none, V 2,5-dichloro-3,6-bis(3-chlorobenzamido)benzoquin-one, "2,5-dichloro3 ,6bis(4-nitrobenzamido}benzoquinone, 2,5 dicl1loro-3,6 bis-( l-dimethylaminobenzamido)henzoqumone, 2,5-dichloro-3,6=bis-(Z-carboxybenzamido)benzoquinone, 2,5-dichloro-3,6-bis(4-carbamyl-benzaniido}benzoquinone, 2,5-dichloro-3,6-bis(4-phenylbenzamidwhenzoquinone, 2,5-dichloro-3,6-bis(4-benzylbenzamido).benzoquinene, 2,5-dichloro-3,6bis(2,3-dimethyl-benzamidwbenzoqui none, 2,5-dichloro-3,6-bis(4-bromobenzamido)benzoquinone, 2,5-dich1oro-3,6-bis(2,4-dibromobenzamido)benzoquinone, 2,5-dichloro-3,6-bis(4-methyl-3-nitrobenzamido)benzo-.

quinone, 2,5-dichloro-3,6-bis(4-bromo-2-nitrobeniamidofiaenzo quinone, 2,5-dichloro-3,6 bis(4-acetamidobenzamido)benzoquinone, 2,5-dichloro-3,6-bis(2,4-dichlorobenzamido)benzoquinone,

2,5- dichloror3,6 bis(2-n1ethyl-4-nitrobenzamido)benzo- 2,Srdichlore-3 ,6 bis(N-rnethylbenzarnido)benzo'quinone,

' '2,5-dichloro-'3,6 bis(2-carboity-S-chloroahilino)benzoqui- 2,5-dichloro-3,6 bisM-carboxyphthaliniido)benzoduinone, 7

"2,5-dichloro-3,6-bis(4-methyl-3-nitro-phthalimido)benzo- 2,5-dichloro-3,6-bis(4-nitro-N-methylbenzamido)benzoquinone, v

2,5-dichlor'o-3,6-bis(4-chloro-N-methylbenzarnido)benzoquinone,

2,5-dichloro-3,6-bis(2-chloro -nitro-N-methylbenzamido) benzoquinone, I v a 1 2,5-dich1oro-3,6=bis(4-nitrobenzamidoyfi benzamidobenzoquinone, V V 2,5-dichloro-3,6 bis(2,3,S-trichlorobenzamido)-6-(4-nitro- 'berizarnido)benzoquinone. V V a f i 7 Further illustrative of an especially preferred embodiment of the presently useful amido-substi-tuted benzoqm none additives are the dichlorophthalimidobenzoquin'ones. These are exemplified for example by. V 2,5-dichloro-3,6-diphthalimidozenzoquinone," 5 2,5-dichloro-3,6bis(4;nitrophthalimid o)benzoquinone, 2,5-dichloro-3,6 bisQ4-chlorophthalimido)benzoquinone, 2,5-dichloro-3,6-bis(4-methylphthalimido) benzoquinone,

2,5 -dichloro-3 -phthalimido-6-benzamidobenzoquinone,

2,5-dichlor0-3-(4-nitrophthalimido)-6-phthalimidobenzoquinone, V V 1 2,5-dichloro-3,6-bis(3-chlorophthalimido)henzoquinone,

.2,5-dichloro-3,6-bis(4-ehlorophthalimido)benzoquin0ne,

, 2,5-dich1oro-3,=6-bis(3-nitrophthalimido)benzoquinone,

2,5 -dichloro-3 ,6-'bis(4dimethylaminophthalimido)benzoquinon'e, '1 i 2,5-dichloro-3,6 bis(4-carbamy lphthalimidoflvenzoquinone, j i I 2,S-dichloro-3,6-bis(4-bromophthalimido)benzoquinone, 2,5-dichloro-3,6-bis(2,4-dibromophthalimido)bennoquiquinone, 2,5-dichloro-3,6-bis(4 brorno 2-nitrophthalimido)benzoquinone, i 2,5-dichloro-3,6-bis(3,4-dichlorophthalimidwbenioq 7 none, r 2,5 dichloro-3,6-bis(3-'nethyl-4-nitrophthalimido)benzo-' quinone, V V v 2,5 dichloro-3,6-bis(3-methyl-5-nitrophtha1imido)benzo-T quinone, e 1, 2,5-dichloro-3,6-bis(3,S-dichldrophthalimido)benzoquinone, 2,5 -di chloro -3,6-bis(3-chloro-5-nitrophthalirnido)benzo quinone, and the like. To provide the lubricant compositions of this invention, the benzoquinones of the nature stated above are combined with a high tempera-tur'elubricant base fluid,

This will be a base oil of lubricating viscosity which remains in the liquid phase attemperatures up to at least about 500 F. In general, the lubricant compositions of this invention will he designed for lubrication of the mov-' ing parts of mechanisms operatingin temperature ranges c5400 F to 760 F. A particularly advantageousbase fluid for use under these conditions comprises the above mentioned polyphenyl'ethers;

The polyphenyl ethers' employed as base fluids in the V compositions of this'invention'have from 3 to 7 benzene rings and from 1 to 6 oxygen atoms, with'the. stated oxy gen atoms joining the benzene rings in chains as: ether linkages. One or more of the benzene rings'in these Vpolyphenyl ethers rnay be hydrocarbyl substituted. The

hydrocarbyl substituents, for thermal stability, must be free of CH and aliphatic CH, so that preferred aliphatic substituents are lower saturatedhydroca'rboii radicals (l to 6 carbon atoms) like methyl and tert-butyl, and pre- 5 V v ferred aromatic substituents are aryl radicals like phenyl, tolyl, t-butylphenyl and a-cumyl. In the latter case, the benzene ring supplied in the hydrocarbyl substituent contributes to the total number of benzene rings in the molecule. Polyphenyl ethers consisting exclusively of chains of from 3 to 7 benzene rings With at least one oxygen atom joining the stated benzene rings in the chains as an ether linkage have particularly desirable thermal stability. Exemplary of the polyphenyl ethers containing aliphatic carbon which are suitable for high temperature base fluids are 3-ring polyphenyl ethers like l-(p-methylphenoxy)-4-phenjoxybenzene and 2 ,4-diphenoxy-l-methylbenzene, 4 ring polyphenyl ethers like bis[p-(p-methylphenoxy)phenyl] ether and bis[p-(p-tert-butylphenoxy) phenyl] ether, and so forth.

Polyphenyl ethers consisting exclusively of benzene rings and including ether oxygen atoms linking said rings are exemplified by the triphenoxy benzenes and arylsubstituted polyphenyl ethers such as biphenylyl phenoxyphenyl ether, biphenylyloxyphenyl phenoxyphenyl ether, dibiphenylyl ether, dibiphenylyloxybenzene, bis(biphenylyloxyphenyl) ether, and the like.

A preferred class of the polyphenyl ethers are those consisting of benzene rings joined in a chain by oxygen atoms as ether linkages between each ring, of the formula C H O(C H O) -C H where n is an integer of from 1 to 5.

Examples of the polyphenyl ethers contemplated in this class are the bis(pheuoxyphenyl) ethers (4 benzene rings joined in a chain by 3 oxygen atoms), illustrative of which is bis(m-phenoxyphenyl) ether. The bis(phenoxyphenoxy) benzenes are particularly valuable in the present connection. Illustrative of these are m-bis(mphenoxyphenoxy)benzene, m bis( p phenoxyphenoxy) benzene, o-bis(o-phenoxyphenoxy)benzene, and so forth. Further, the polyphenyl ethers contemplated herein include the bis(phenoxyphenoxyphenyl) ethers such as his [m-(rn-phenoxyphenoxy)phenyl] ether, bis [p- (p-phenoxyphenoxy)phenyl] ether, and m-(m-phenoxyphenoxy) phenyl m-(o-phenoxyphenoxy)phenyl ether, and the his (phenoxyphenoxyphenoxy)benzenes such as m-bis [m-(mphenoxyphenoxy phenoxy] benzene, p-bis [p- (m-phenoxyphenoxy)phenoxy]benzene and In bis [m (p phenoxyphenoxy phenoxy] benzene.

The preferred polyphenyl ethers are those having all their ether linkages in the meta-positions since the allmeta-linked ethers are particularly advantageous because of their wide liquid range and high thermal stability. However,- mixtures ofthe polyph'enyl ethers, either isomeric mixtures or mixtures of homologous ethers, can also advantageously be used in some applications, especially where particular properties such as lower solidification points are required. Mixtures of polyphenyl ethers vin which the non-terminal phenylene rings are linked have been found to be particularly suitable to' provide compositions with wide liquid ranges. f the mixtures having only meta and para linkages, a preferred polyphenyl ether mixture of this invention is the mixture of bis(phenoxyphenoxy)benzenes wherein the non-terminal phenylene rings are linked through oxygen atoms in the meta" and paraposition, and composed by weight of about 65% m-bis [m-phenoxyphenoxy]benzene, 30% iii-[(mphenoxyphenoxy) (p phenoxyphenoxy) jbenzene and m -bistp-phenoxyphenoxy) benzene. Such a mixture solidifies at below room temperature (that is, below about 70 F.) whereas the three component-ssolidify individually at temperatures above normal room temperatures.

The aforesaid polyphenyl ethers can be obtained by known procedures such as, for example, the Ullman ether synthesis, which broadly relates to ether-forming reactionswherein alkali metal phenoxides such as sodium and potassium phenoxide are reacted with aromatic halides such as bromobenzene in the presence of a copper catalyst such as polyethylene glycols.

such as metallic copper, copper hydroxides, or copper salts.

The high temperature, oxygenated carbonaceous base fluids employed in the compositions of this invention may also comprise a synthetic ester base fluid. These are fluids of lubricating viscosity and thermally stable to at least about 400 R, which are esters of alcohols containing at least 4 carbon atoms and which generally contain more than one ester group. They may be esters of polyhydric alcohols, of polybasic acids, or both.

The stated synthetic esters are generally aliphatic in nature, as distinguished from the essentially. aromatic nature of the polyphenyl ethers, and their properties and response to additives have correspondingly been found to be usually of a different kind. Unexpectedly, however, .the presently contemplated quinone additives have been found to provide significant improvement in the properties of the stated ester type of base fluid also. Thus it appears that compositions comprising an adjuvant amount of a quinone as defined above combined with a high temperature lubricant base fluid which, broadly, is an oxygenated carbonaceous base fluid are novel and valuable products with useful properties, and this invention extends to the provision of the stated general class of compositions.

Ester fluids with particularly advantageous low temperature viscosity properties, which flow readily at temperatures-as low as -30 F., are provided by the diesters of dibasic acids. Ester lubricants of the dibasic acid ester type are illustrated by diesters of long chain dicarboxylic acids like azelaic acid with long-chain branched primary alcohols of the C to C range. The synthetic ester lubricants also frequently include the esters of long chain monobasic acids such as pelargonic acid with glycols Complex esters are also formed by linking dibasic acid half esters through a glycol such as dipropylene glycol, a polyethylene glycol of 200 molecular weight, and so forth. Permutation and com bination of these methods of-forming polyester type lubricant fluids have been reported to be valuable and also, it is common practice to achieve desired properties in the ultimate base fluid by blending different polyester products. Simple esters providing suitable fluids can be exemplified, for example, by bis(2-.methylbutyl) sebacate, bis(l-methyl-4-ethyloctyl) sebacate, bis(2-ethylhexyl) sebacate, 'dipropylene glycol dipelargonate, the diesters of acids such as sebacic, azelaic and adipic acid with complex C -C primary branched chain alcohols such as those produced by the 0x0 process, polyethylene glycol 200 bis(2-ethylhexyl sebacat'e), diisoamyl adipate, 1,6- hexamethylene glycol di(2-ethylhexanoate), bis(dimethylamyl) azelate and so forth.

Ester fluids with particularly good high temperature oxidation resistance are provided by neopentyl polyol esters. The alcohols from which these esters are derived have the carbon structure of neopentane, with a central carbon atom surrounded by 4 substituent carbon atoms. Included in the neopentyl polyols are neopentyl glycol, trimethylolethane, trimethylolpropane and pentaerythritol. Generally, the base fluids comprising neopentyl polyol esters are the esters with monocar-boxylic acids. Such esters are generally more oxidatively and thermally stable than the dibasic acid esters. The useful esters of the neopentyl polyols include, for example, the esters of trimethylol propane, neopentyl glycol and pentaerythritol with normal, branched chain and mixed acids having chain lengths varying from C to C Thus, an illustrative series of esters are trimethylolpropane tri-n-pelargonate, trimethylolpropane tricaprate, trimethylolpropane tn'caprylate, the trimethylolpropane triester of mixed octanoates, and the like. 7

For further description of still other ester fluids adapted for use as lubricant base stocks and useful in the provision of the blends of this invention, reference may be stability at elevated temperatures.

.neoheptanoic acid. I V V Compositions of the stated valuable nature and pro-.

vided by combining 25-75 weight percent of the ester base fluids with 75-25 weight percent of the polyphenyl ethers.

As noted hereinabove, additive activity and. particularly 7 made, for example, to the discussion in Gunderson et al., Synthetic Lubricants (Reinhold, 1962).

oxygenated carbonaceous base fluids employed in the.

present compositions may consist essentially of a polyphenyl etherbase fluid alone,- a synthetic ester base fluid alone, or a combination of the polyphenyl ether with za' synthetic ester base fluid. The polyphenyl ethers are not generally miscible with other base fluids: they do not dissolve more than about.5% by weight mineral oil, for examp e. Attempts to blend silicones with the phenyl ether base fluids have shown that only a few of this class of fluids are miscible with the polyphenyl ethers, and then to a limited extent. However, it'has been found that the polyphenyl ethers can be combined with other oxygenated carbonaceous base fluids to providehomogeneous fluids.

A deficiency of the polyphenyl ether base fluids having exceptional thermal and oxidative stability, as exemplified by the bis(phenoxyphenoxy)benzenes discussed above, is

lack of fluidity at low temperatures. The fluid range of these materials is unusually wide, encompassing the range from below 100 F. toabove 800 F. However, the pour point of certain of these particularly stable fluids is above 0-F., whereas for'lubricant use, for example, ability to flow down to temperate climate winter temperatures such as 0' F. is desirable. It has been found that compositions comprising combinations of ester. base fluids and the polyphenyl ethcrs. can be provided which have the desired fluidity at low temperatures. 7

aromatic hydrocarbons, includingalicyclic ringsrand alkylated alicyclic rings, have also been observed to possess fair stability'under high temperature stress conditions, Mineral oils, paraflinic and naphthenic, can also be provided with substantially improved high temperature sta bility as compared to the less refined oils in common use undcr less severe conditions, by super-refining. Superrefining is the removal or substantial reduction of the polar impurities, 'uns'aturates and unstable hydrocarbon.

structures by exhaustive hydrogenation, severe acid treatment, adsorption, or a'combination of these. processes. The effects include improvement in thermal stability'and metal corrosion tendencies dirt formation and pressure buildup due to decomposition as comparedto conven tionally refined mineral oils. are approximately the same for the super-refined mineral oils as for the ester lubricants. 'Useful'm'ineral oils for lubricant compositions are, as is "known in the art, the petroleum products boiling at temperatures above the kerosene range. A typical'mineral oil base for extreme pressure lubrication will becharacterized by a viscosity of 35350 Saybolt Universal seconds at 2127 F., a viscosity index in the range of from to 150 and a flash point of between about 275 and 600 F.

Silicon-base high-temperature lubricant fluids are exemplified, for example, by silanes such as n-dodecyl tri-n- The lubricant fluids which have been found to blend with the phenyl ethers of good thermal and oxidative stability include various esters. -tis particularly desirable to provide blends having thermal and oxidative stability at least approaching the stability of the polyphenyl ethers,

in this connection, especially valuable base fluids have been found to be provided by combinations of a polyphenyl ether with a neopentyl alcohol ester. These compositions possess both fluidity at low temperature and The preferred polyphenyl others for use in this connection are the bis(phenoxyphenowfienzcnes, of the composition C H5O-( C H O) C H where each Ci l-I is a phenyl and each G l-I is a phenylene radical. Those with the ether linkages between benzene rings in meta positions, partly or wholly, are especially preferred. The stated neopentyl esters are estersof neopentyl alcohols such as pentaerythritol, trimethylolethane,'trimethylolpropane and neopentyl glycol with straight chain, branched chain and mixed C C acids such as n-heptanoic and lubricity-improving additive activity is usually not found to be general to diflerent classes of lubricant base fluids. However, as will appear from the examples hereinafter, compositions comprising the presently employed 'benzo- 'quinones have unexpectedly been found to-possess improved properties compared to the base stock alone with base oils of diverse kinds. So far as is known, the presently provided compositions, consisting essentially of a benzoquinone of the above-described nature and a" base oil of lubricating viscosity which remains in the liquid phase at least up to about 500 F., are novel materials,

7 .Thus. in its broader aspects, this invention relates'torprovision of compositions of the stated scope, using various base stocks of the stated description. For example, the base stock may be a hydrocarbon oil, a silicon-containing .oil, va fluorinated oil, and so forth.

illustrative of contemplated hydrocarbon lubricant base ifluids are the aromatic hydrocarbons, particularly condense d ring structures such as biphenyl, alkylbiphenyls such as isopropylbiphenyl, and terphenyls, quarte'rphenyls,

the alkyl derivatives of these polyphenyls such as dimethyl' terphenyl, and the like. Hydrogenated derivatives of these decyl silane and diphenyl di-n-dodecyl silaneythe' silicone polymer fluids such as dimethyl silicone and methyl phenyl silicone polymers, and disiloxanes and tetraalkyl orthosilicate esters such as'di-tert-butyl di-Z-ethylhexyl orthor silicate, 1,3-di-tert-butoxy-l ,'l,'2,2-tetra(2-pentoxy) disilox- 'ane, tetra(methylphenyl) silicate, tetraphenyl silicate',.:

'tetra(2,-ethy lhexyl) silicate, and so forth.

Illustrative of fluorine containing base fluidsare fluorinated esters like bis'(perfluoroamyl)phthalate, bis(perfluorohexyl) 3-methyl glutarate, and Ll-H-nonafluoropentyl nonaiiuoropentanoate; and the polymers of'chlorotrifluoroethylene, for example, with average molecular weights'of about 5001000, and so forth. 7

The compositions of'thisinvention will consist essentially of a major proportion of the basefluid and a minor proportion of the benzoquinone additive. In general, when the ultimate formation of the base'fluidto be introduced into the equipment tobe lubricated has. been made, the

concentrations to be employed for eifective improvement of the base fluid properties by the benzoquinone additive Wlll be generally between about 0.01% 'and.10.0% by weight. The precise quantity will depend on the nature of the adjuvant compound and of the base fluid, and upon the adjuvant effect desired. Thus the most elfective concen- :tration for diminishing wear of moving metalparts .and 7 that for increasing the pressure load which the lubricated parts can exert without seizure may not be the same. In-

anycase, at least an adjuvant amount sufficient to produce an improvement in at least one of the lubricant properties'of the base fluid will be employed; Whether or not f the desired adjuvant eflect is obtained isreadily determined by use of conventional testing procedures known to 7 those skilled in the art. 1 t

It is frequently beneficial to employ a'combination of different additives in formulating ultimate lubricant compositions. Forexample, nitrogenous compounds such as phenothiazineand derivatives thereof :are often employed to' increase oxidation resistance, and-polymeric materials such as polya'crylic esters may be employed as viscosity index improvers, sludge dispersants, and so forth. It

is to be appreciated that such additional'beneficial additive may anddesirably will be present in lubricant composi- 'tions embodying the present invention.

In the following examples, the tests employed to determinethe reported adjuvant effects of the quinone com pounds when employed with the lubricant base fluids are conducted as follows: i

The anti-wear. and extreme pressure lubrication characteristics of the lubricant compositions are evaluated by Oxidation rates at 500 F.

means of the Shell 4-Ball Extreme Pressure Tester and the Shell 4-Ba1l Wear Machine. These testers include four balls of stainless steel arranged in. the form of an equilateral tetrahedron. The 'three lower balls are held immovably clamped in a holder to form a cradle in which thefourth upper'ball is caused to rotate at 1200-1800 r.p.m. about a vertical axis in contact with the three. lower stationary balls. The contacting surfaces of the balls are immersed in the test fluid, which is held in a cup surrounding the assembly. A modified cup and heater assembly is used to evaluate lubricants at elevated temperature and provisions are made to permit testing under an inert atmosphere: see The Study of Lubrication Using the Four Ball Type Machine, by R. G. Larsen, Lubrication Engineering, vol. 1, pages 35-43, 59 (August 1945).

For measurement of wear, the rotating ball is rotated under a load of 40 kilograms (kg.) for 1 hour at each of the temperatures for which wear scar diameters worn in the surface of the three lower stationary balls are reported.

For determination of the extreme pressure properties in the 4-Ball EP Tester, the upper ball is rotated while the load is gradually increased by increments of kg. until the balls are Welded together in a 1 minute test period.

Additionally, the present compositions have been submitted to the Falex antiweld test: see the articlesby V. A. Ryan in Lubrication Engineering September 1946 and by S. Kyropoulos in Refiner Natural Gasoline Manufacturer, vol. 18, pages 320-24 (1939), and Amer. Soc. Test. Matls. D-2, Section V, Tech. K. A steel journal pin is rotated by a driving shaft at 290 r.p.m. in jaws (V-bearing steel blocks) through which a constantly increasing load is applied, with ratchet means compensating for wear of the journal pin during the test. The assembly is immersed in the lubricant. The load at failure due either to seizure or to wear at a rate faster than the load-increasing rate is recorded.

Example 1 A lubricant composition is prepared by combining 2,6- dianilino-3,6-dichloro-1,4-benzoquinone with a polyphenyl ether of the following composition, by weight:

65 m-bis (m-phenoxyphenoxy) benzene,

30% rn-[-(m-phenoxyphenoxy)(p-phenoxyphenoxy)] benzene,

5% m-bis(p-phenoxyphenoxy)benzene,

in a proportion of 1 gram (g.) of the quinone to 100 of the base fluid.

A portion of the base fluid used to provide the abovedescribed composition is reserved, free of additive, and run through the same sequence of tests, to provide a basis for comparison.

Using the base fluid alone, in the extreme pressure test, the balls weld at a pressure of 150 kg.

Employing the lubricant composition described above consisting of 1% of the quinone compound combined with the same polyphenyl ether, the weld point found is 490 kg.

Using the Shell 4Ba1l Wear Tester, the wear scar diameters determined for the lubricant composition of this example including the stated quinone and for the base fluid without additive are as follows:

Wear Scar Diameter, mm.

With additive 1. 45 1. 71 Without additive 1. 82 2. 92

Example 3 10 The solution of the additive in the polyphenyl ether is subjected to test of its extreme pressure and wear properties in the Shell 4-Ball'Testers, with results as follows:

Wear Scar Diameter, Weld mm. Point, kg.

With additive.-. 400 1. 45 2. 05 Without additive 150 1. 82 2. 92

Example 3 of 2,5-bis(4 nitrophthalimido)-3, 6 dichloro 1 ,4-benzoquinone.

The average failure load of the base stock Without additive is 500, whereas for each of compositions (2) and (3) with quinonic additives included, it is 2500.

Example 4 This example describes preparation and properties of a lubricant composition which is a solution of a dichlorodiaminoqu-inone in an oxygen-containing base fluid of the ester type.

A saturated solution is prepared of 2,5-dichloro-3,6- bis(-o-chloroanilino)-1,4-benzoquinone in trimethylolpropane tnienanthate, containing a concentration of about 0.75 g. of the quinone per g. of the base fluid.

For evaluation of the ability of the additive to increase .the load-carrying ability of the base stock and improve wear chanaoteristics, the tests employed are the Shell 4-Ball Extreme Pressure and Shell 4-Ball Wear Test described above. In the extreme pressure test, the weld point of the 'base stock Without additive is 130 kg, while the weld point for the composition in which the base stock contains the dissolved quinone compound is 210 kg. Measurement of the Wear scar diameter gives values of approximately 1 mm. at 167 and at 400 F, (1.07 and 1.03 mm. respectively), whereas for the ester without additive, the 400 F. wear scar diameter is 2.29 mm.

Example 5 This example describes lubricating characteristics of compositions consisting of a mineral oil and a quinone in accordance with the invent-ion.

Lubricant compositions are provided by dissolving 2,5- d-ichloro-3,6-bis(o-chloroanil-ino)-1,4 benzoquinone in a naphthenic white oil described as MLO-7357, which has a pour point of 18 F., viscosity 80.57 cps. at 100 F., 8.51 cps. at 210 F., to the limit of the room temperature solubility of the quinone in the oil, producing a concentration of about 0.25 g. per 100 g. of base oil,

Without additive, this oil has a weld point of kg. and produces wear scar diameters of 1.73 mm. at 167 F. and 3.57 at 400 F. The composition comprising the stated quinone has a weld point of 210-220 kg. and the wear scar diameter is 0.83 mm. at 167 F. and 1.0 mm. at 400 F.

While the invention has been described with reference to specific preferred embodiments thereof, it is to be appreciated that modifications and variations can be made without departing from the scope of the invention, which is limited only as defined in the appended claims.

1. A composition consisting essentially of (1) aimajor What is claimed is amount of a base oil of lubricating viscosity whichre' mains in the liquid phase up to at least'about 500 F, and

radicals, in an amount sufiicient to improve'the extreme pressure and anti-Wear characteristics of said base oil.

2;I he composition ofclaim 1 wherein said base oil is selected from the class consisting of polyphenyl ether and synthetic ester base fluids.

" 3. The composition of claim 2 wherein said benzoquinone is a di(aryla-mino)dichloro-1,4-benzoquinone.

4; The composition of claim. 3=Wherein said Vbenzoquinone is 2,5dichloro3,6 bis( o-chloroanilino)benzoquinoner I .i a V '5. The composition'of claim 2 wherein said'base oil comprises a polyphenyl ether base fluid. V

6. A functional fluid composition consisting essentially of a polyphenyl ether base fiuidconsisting of fromSto 7 benzene rings joined in a chain by oxygen atoms as ,ethe'r linkages between each ring, and an amount of .a di(arylamino)dichloro-1,4-benzoquinonel sufiicient to improve a lubricating characteristic of the polyphenyl ether base fluid selected from the group consisting of extreme pressure and anti wear characteristics. T

7. The composition of claim 6 wherein said .benzoquinone. is 2,S-dichloro-3,6-dianilino l,4 benzoquinone.

1.21 .7 8. The composition of claim 7 inwh-ich the said polyphenyl ether, base fluid consists of a' mixture of his (phenoxy-phenoxy)benzenes. a 3

9. The composition of claim 21 wherein said benzoquinone is a bis(-arylcarbonyhsubstituted-amino) dichloro- 1',4-benzoquinone. i

10. A functionalfiuid composition inwhich'th ecbase 'fluid comprises a major amount of a polyphenyl ether consisting of from 3 to 7 benzene rings joined in a chain by oxygen atoms as ether linkages between each ring, and

an amount of a Ibis(arylcarbonyl-substituted-amino)dichloro-lA-benzoquinone sufifi'c-ient to' improve a lubricating characteristic of said polyphenyl ether base fluid 'selected from the class consisting of extreme pressure and anti-wear characteristics,

11. The compositionof claim 10 in which said benzoq-uinone is 2,5-dicl1lor1o-3,6-'bis(4 nitrophthalimido)-1,4- benzoquinone. a f

References Citedby the Examiner UNITED STATES PATENTS 7 2,134,505 10/38 Brunner et a1. 260- 396 XR 2,367,344 1/45 Evans 252'51.5 3,036,071 5/62 Frey ct a1 26Q 396 XR 3,037,015

DANIEL E. WY-MAN, Primary Examiner. 

1. A COMPOSITION CONSISTING ESSENTIALLY OF (1) A MAJOR AMOUNT OF A BASE OIL OF LUBRICATING VISCOSITY WHICH REMAINS IN THE LIQUID PHASE UP TO AT LEAST ABOUT 500*F., AND (2) A DIAMINODICHLOROBENZOQUINONE HAVING AN AROMATIC RADICAL ATTACHED TO EACH OF THE AMINO NITROGEN ATOMS SELECTED FROM THE CLASS CONSISTNG OF ARYL AND ARYLCARBONYL RADICALS, IN AN AMOUNT SUFFICIENT TO IMPROVE THE EXTREME PRESSURE AND ANTI-WEAR CHARACTERISTICS OF SAID BASE OIL. 